Low vitamin D results in more aggressive melanoma

Photophobic doctors and public health officials warn you to stay out of the sun to reduce your risk of malignant skin cancer. But in a new study, men and women with low vitamin D levels (one real result of staying out of the sun) developed far more aggressive melanomas. I’ll talk more about that study in a moment.

Clearly, the ill-advised sun-avoidance guidelines contribute to the epidemic of vitamin D deficiency raging around the globe. Plus, studies show low vitamin D raises your risk of developing many different types of cancer. Including skin cancer. Low vitamin D also raises your risk of depression, dementia, heart disease, metabolic disorders, and nervous system diseases such as multiple sclerosis (MS).

Now let’s look a little deeper into the specific problem of skin cancer…

As I often report, 91 percent of all skin cancer growths aren’t malignant. They don’t  invade. They don’t metastasize. And they will never kill you.

Doctors can easily detect these growths in regular physical exams. Furthermore, they can easily remove these growths with a simple scrape of the skin. Frankly, we shouldn’t even call them “cancer” at all.

You see, pathologists use a grading system to assess cancer on a scale of 1 to 10 for increasing “carcinogenicity.” But they had to make up the grade of “one-half” because even these individual skin “cancer” cells don’t look like cancer.

The one truly malignant form–called melanoma–makes up just 9 percent of all the cases broadly classified as skin cancer. This type of skin cancer does invade, spread, and kill.

But we recently got a bit of good news about this deadly form of skin cancer: Vitamin D may protect you against it.

The new study took place in Brisbane, Australia–the skin cancer capital of the “western” world. It included 100 men and women newly diagnosed with melanoma skin cancer.

The researchers took a three-step approach:

First, they assessed prior cancer risk factors through medical history. They adjusted for factors that might influence the data, including age, sex, skin type, body mass index, and season at diagnosis.

Then, they carefully measured the thickness of the skin cancers. In melanoma, the thickness of the tumor, together with appearance of individual calls, is the major factor for assessing the prognosis for mortality or survival. So the thicker the growth, the more aggressive and lethal the cancer.

Lastly, the researchers measured the patients’ vitamin D levels with a blood serum test for 25(OH)D.

They found men and women with low vitamin D were more likely to develop thicker malignant melanoma tumors. To be more specific, men and women with lower blood serum 25(OH)D levels had a four times greater risk of developing a thicker melanoma tumor than men and women with higher levels. And men and women with even lower blood serum levels had a five times greater risk!

Bottom line?

Men and women with higher vitamin D had more treatable malignant melanoma associated with better prognosis and higher survival.

They also found that sun exposure, sunburns, and other kinds of sun damage to the skin had no effect on the thickness of malignant skin cancer tumors.

Clearly, the connection between sun exposure and skin cancer, even with malignant melanoma, is more complex than the photophobic “amen chorus” would have us believe.

Yes–research shows UV radiation is a risk factor for malignant melanoma. But science also knows that certain UV radiation exposure activates vitamin D production in the skin…and as this study shows, vitamin D has a positive effect on the prognosis of melanoma.

Furthermore, previous lab studies show vitamin D minimizes tumor growth, prevents growth of cancer cells, and causes programmed death (“apoptosis”) of cancer cells.

The way I see it, the D-bate is over.

Spend 15 minutes outside each day without sunscreen to activate vitamin D production on your skin. Also, make sure to take 10,000 IU of vitamin D daily to keep your skin, body and mind healthy.

Next time, I’ll report on new findings about the dangers of many popular sunscreens.


“Vitamin D deficiency at melanoma diagnosis is associated with higher breslow thickness,” PLoS One. 2015 May 13;10(5):e0126394